today national investigative correspondent jeff rossum is here with that story. >> we've heard a lot about adam lanza and we've heard a lot about his mother, but now we have new information about his relationship with his father, peter. a source close to the family tells nbc news adam had cut off communication with his dad, even refusing to see him. in the chaotic hours after adam lanza's rampage, a local reporter showed up at his father's doorstep to break the news. >> his face went from patient to surprise to horror. it was pretty clear to me that he was surprised that somebody he loved was involved with what was happening up in newtown. >> reporter: peter lanza is a successful finance executive at ge, part owner of nbc universal. a source close to the family says in 2001, he separated from adam's mother, nancy, but he still saw adam every week. in 2009, the lanzas officially divorced. adam was 17. >> they were the type of parents, even when they were married as well as being separated, if the kids had a need, they would definitely fill it. >> reporter: but the source says by 2010,